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Golden Rice
'Golden rice" Group of European scientists, pioneered by Dr. Ingo Potrykus of the Swiss Federal Institute of Technology and Dr. Peter Beyer of the University of Freiburg in Germany published scientific detail of their research in January, 2000. In 2005, Golden Rice 2, which produces a higher concentration of beta-carotene than the original golden rice, was revealed. Golden rice is a genetically engineered (GE) rice variety that has been developed by industry or proponents with the claim to provide a more sustainable, inexpensive and effective solution to vitamin A (beta-carotene) deficiency. Golden Rice is genetically engineered to biosynthesize beta-carotene, a precursor of vitamin A, in the endosperm the edible parts of the rice.This genetically modified (GMO) rice is believed to supplement vitamin A deficiency in countries or areas with shortage of dietary vitamin A; a silent killer of malnourished children and pregnant mothers in some developing countries Discovery of Golden rice The rice plant can photosynthetically create beta-carotene within its leaves, but not in the endosperm, where photosynthesis doesn’t take place. The discovered that a single phytoene desaturase gene (bacterial CrtI) can be utilized to create lycopene from phytoene in GM tomato, as opposed to having to introduce the multiple carotene denaturizes that are usually utilized by higher plants. Lycopene is then cyclized to beta-carotene via the endogenous cyclase in Golden Rice. Transforming rice with only two beta-carotene biosynthesis genes created the Golden Rice: psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus) and crtI (carotene desaturase) from the soil bacterium Erwinia uredovora.The insertion of a lyc (lycopene cyclase) gene was thought to be required, but further research proved it’s already being produced in wild-type rice endosperm. The psy and crtI genes were transformed into the rice nuclear genome and placed under the control of an endosperm-specific promoter, so they are only expressed in the endosperm. The exogenous lyc gene has a transit peptide sequence connected so it is targeted to the plastid, where geranylgeranyl diphosphate formation takes place. The bacterial crtI gene was a significant inclusion to accomplish the pathway, since it can catalyze multiple steps in the synthesis of carotenoids up to lycopene, while these steps need more than one enzyme in plants. The end product of the engineered pathway is lycopene, but if the plant accumulated lycopene, the rice would be colored red. Recent analysis has shown the plant’s endogenous enzymes process the lycopene to beta-carotene in the endosperm, giving the rice the distinguishing yellow color for which it is named. The original Golden Rice was named SGR1, and under greenhouse conditions it generated 1.6 micrograms per gram of carotenoids ( Xudong Ye, et.al 2000). Debate and controversy over Golden rice Proponents of "Golden rice" like The biotech companies are claiming that genetically engineered (GE) crops, like golden rice, will solve problems of malnutrition. The malnutrition claim has drawn support from every major agricultural biotech company, the Consultative Group on International Agricultural Research (CGIAR), the US Agency for International Development (USAID), and its main funder, the Rockefeller Foundation. On the other hand skeptics like environmental activist have an alternative view points and concerns.That GMOs like the Golden rice, is an exploitation of the environment, patent control, increase poverty,health risk. According to report in PBS News, that was conducted by Miles O'Brien On August 8, 2013 an experimental plot of golden rice being grown in the Philippines was uprooted by protesters, which opposes GMOs primarily out of fear they will contaminate other crops. Clinical trials and research finding According to a conclusion arrived at and published in American Journal of Clinical Nutrition, after a clinical trial result of Golden rice in 2009. Humans can, effectively convert beta Carotene that was derived from Golden rice, just like beta-carotene derived from other sources, to vitamin A. Suggesting that Golden rice will be able to supply dietary allowance of vitamin A. As a result of this finding, a group of scientist stated “ there is now a body of evidence that shows that GM crop/food production is highly prone to inadvertent and unpredictable pleiotropic effects, which result in health damaging effects when GM food products are fed to animals. More specifically, our greatest concern is that this rice, which is engineered to overproduce beta carotene, has never been tested in animals, and there is an extensive medical literature showing that retinoid that can be derived from beta carotene are both toxic and cause birth defects.” References Paine, J., Shipton, C., Chaggar, S., & Howells, R. (2005, March 27). Improving the nutritional value of Golden Rice through increased pro-vitamin A content. Retrieved October 8, 2014, from Ye, X; Al-Babili, S; Klöti, A; Zhang, J; Lucca, P; Beyer, P; Potrykus, I (2000). "Engineering the provitamin A (beta-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm". Science 287 (5451): 303–5